The converse of the Pythagorean theorem is also a true statement: If the sum of the squares of the lengths of two sides of a triangle is equal to the square of the length of the third side, then the triangle is a right triangle. Use the distance formula and the Pythagorean theorem to determine whether the set of points could be vertices of a right triangle.
The points $(-3,4),(2,-1),(5,2),$ and $(0,7)$ are vertices of a quadrilateral. Show that the quadrilateral is a rectangle. (Hint: Show that the quadrilateral's opposite sides are the same length and that the two diagonals are the same length.)